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course Phy 201
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course Phy 201
experimentUses: washer, thread, analog clock, ruler or meter stick
Construct a pendulum using washer and thread. Make 1-minute counts for pendulum lengths (measured from the position at which the thread is held to the center of the washer) equal to three different lengths:
* the the distance from your wrist to your fingertips
14cm
* the distance from your elbow to your fingertips
30cm
* the distance from your shoulder to your fingertips
56cm
Be sure to measure the length of each pendulum you time.
Report the pendulum lengths and the corresponding numbers of counts:
24.5cm, 60 cylces
18cm, 70 cycles
10cm, 96 cycles""
Analysis:
Graph your 1-minute count vs. length, and sketch a smooth curve representing the trend of your data.
Here is a link to the graph, I could not get the graph to paste into notepad. http://i1005.photobucket.com/albums/af177/ag1972/b.jpg
Using your graph estimate the number of counts for a pendulums of length 52 cm, and another of length 13 inches. Estimate also the lengths corresponding to pendulum counts of 30 and 50.
About a 40 count for a length of 52cm and a count of about 55 for a length of 13in.
A length of about 60cm for a count of 30 and a length of about 40cm for a count of 50.
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Determine the period of each of your three pendulums, i.e., the time required to complete 1 oscillation. A oscillation is from extreme point through equilibrium to opposite extreme point.
1 cycle per second for the 24.5 cm pendulum.
1.17 cycles per second for the 18cm pendulum.
1.6 cycles per second for the 10cm pendulum.
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Sketch a graph of period vs. length, showing your three points, and sketch a smooth curve to fit your graph.
As the length of the pendulum increased, the number of cycles decreased.
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Use your graph to estimate the period of a pendulum whose length is 26 cm, and also the length for which the period would be 1.2 seconds.
A pendulum with a length of 26cm would have a period of about 0.9seconds. A pendulum with a period of 1.2seconds would have a length of about 17cm.
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What is the uncertainty in the number of counts made, and to what do you attribute the uncertainty?
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What is the approximate average percent uncertainty in your counts?
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Self-critique (if necessary):
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Self-critique rating:
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&#This looks good. Let me know if you have any questions. &#